During May-June 2014, a remediation crew from V3 Companies performed dig/haul of petroleum-impacted soil on Parcel D within the NE Park site . The objective of the work was to remove soil impacted with levels of total petroleum hydrocarbons (TPH) that exceed site-specific Illinois EPA cleanup standards. Summary of findings of fieldwork below and can also be accessed online.
Soil Remediation Activities
The cleanup work was performed in accordance with the IEPA-approved Remedial Action Plan (RAP) consisted of the excavation and haul-off of approximately 300 tons of TPH-impacted soils, and landfill disposal of these soils as a non-hazardous certified special waste.
After the impacted soils were removed, V3 collected soil verification samples from the excavation sidewalls and bottom. Soil analytical results for the verification samples were well below the site-specific soil TPH cleanup objective. No further soil remediation is required to address the issue.
Exploration for the Suspected Storm Sewer
While the cleanup excavation was open, V3 also explored the area where an suspected concrete storm sewer was previously observed in a soil boring. The excavator encountered concrete debris and a concrete floor slab at a depth of approximately 10 feet below grade, where water was observed flowing from beneath the slab. Remnants of the original soil boring were also encountered in this area. After further digging, no actual storm drain or sewer was found. It is evident that the concrete slab and groundwater found in the excavation were the features observed in the previous soil boring. Thus, there is no evidence of a storm sewer in this area. The materials were actually a piece of the former building foundation from when the site was a brickyard long ago. No further work is required to address this matter.
The remediation excavation was subsequently backfilled with the stockpiled overburden soils and clean soil that was imported to the site. The area was rough-graded smooth to match the surrounding ground surface.
GW Monitoring Well Installation
One permanent groundwater monitoring well was installed down-gradient from the TPH cleanup area. No obvious evidence of TPH impacts was observed in the well boring soil samples, and no visual evidence of petroleum product or impacts was observed in the groundwater samples. Soil samples were collected for laboratory analysis of BTEX, PAHs and TPH. Groundwater samples were analyzed for BTEX and PAHs.Post Remediation Activities
Soil analytical results were reported to be non-detect for BTEX and well below the site-specific TPH soil cleanup objective. Groundwater analytical results were reported to be non-detect for BTEX and PAHs. No further action is required with respect to groundwater down-gradient from the cleanup area.
The cleanup activities and results will be documented in the forthcoming Interim Remedial Action Completion Report (RACR), which will be submitted to the Illinois EPA Site Remediation Program for review in the 1st week of July.